This application claims the priority right under Paris Convention of Japanese Patent Application No. Hei 11-165902 filed on Jun. 11, 1999, the entire disclosure of which is incorporated herein by reference.
1. Field of the Invention
The present invention relates to a phase shift mask for use in performing exposure, and transfer on a fine pattern and a phase shift mask blank as the mother material of the mask, particularly to a halftone phase shift mask and a phase shift mask blank.
2. Description of the Related-Art
For the high integration of DRAM starting with 1 Mbit, in these days, the mass production system of 64 Mbit. 256 Mbit DRAM has been established. In this technical innovation, an exposure light source has been shortened in wavelength from g ray (436 nm) to i ray (365 nm) of an ultrahigh pressure mercury lamp. Still at present, the reduction of the exposure wavelength has been studied aiming at higher integration. However, in the usual photolithography method, when the exposure wavelength is shortened, the resolution is improved, but the focus depth is decreased. This causes a problem that the burden on the design of the optical exposure system is increased, the process stability is remarkably deteriorated and that the product yield is adversely affected.
A phase shift method is one of ultra-resolution pattern transfer methods effective for the problem. In the phase shift method, a phase shift mask is used as a mask for transferring a fine pattern.
The phase shift mask is constituted, for example, of a phase shifter part forming a pattern part on the mask, and a non-pattern part (substrate exposure part) in which no phase shifter is present. By shifting the phase of a light transmitted through both part by about 180xc2x0, mutual light interference is caused in a pattern boundary part, and this enhances the contrast of a transferred image. Furthermore, by using the phase shift method, the focus depth can be increased to obtain a necessary resolution. As compared with a transfer process using the ordinary mask provided with a usual light screen pattern of a chromium film, and the like, even when the same wavelength light is used, the resolution can be improved and additionally the process applicability can be enlarged.
The phase shift mask is roughly classified into a complete transmission type (Shibuya/Levenson type) phase shift mask and a halftone phase shift mask for practical use in accordance with the light transmission properties of the phase shifter part. In the former, the transmittance of the phase shifter part is equal to that of the non-pattern part (substrate exposure part), the mask is substantially transparent to the exposure wavelength, and it is said that the mask is generally effective for a line and space transfer. On the other hand, for the latter, the transmittance of the phase shifter part is of the order of several percentages to several tens of percentages of that of the non-pattern part (substrate exposure part), and it is said that the mask is effective for forming a contact hole or an isolated pattern in a semiconductor manufacture process.
FIG. 1 shows the basic structure of a halftone phase shift mask blank, and FIG. 2. shows the basic structure of a halftone phase shift mask. Additionally, the description of a reflection preventive layer, an etching stop layer, and the like for use in the lithography process is omitted.
The halftone phase shift mask blank is constituted by forming a semitransparent film (halftone phase shifter film) 2 on a transparent substrate 1. Moreover, the halftone phase shift mask is constituted of a phase shifter part 3 forming a pattern part on the mask, and a non-pattern part (substrate exposure part) 4 in which no phase shifter is present. Here, the phase shifter part 3 shifts the phase of the exposure light transmitted in the vicinity of an edge to fulfill the function as the phase shifter, and performs a light screen function for substantially intercepting the exposure light with respect to a resist on a transfer substrate.
The halftone phase shift mask includes a single-layer halftone phase shift mask which is simplified in structure and which is easily manufactured. Examples of the single-layer halftone phase shift mask include: a mask comprising a phase shifter formed of chromium-based materials such as CrOx, CrN, CrOxNy, CrxONyCz as described in Japanese Patent Application Laid-Open No. 127361/1993; a mask comprising a phase shifter formed of MoSi-based materials such as MoSiO and MoSiOn as described in Japanese Patent Application Laid-Open No. 332152/1994; and a mask comprising a phase shifter formed of SiN or SiO-based materials as described in Japanese Patent Application Laid-Open No. 261370/1995.
In recent years, with the shortening of the exposure wavelength, the halftone phase shift mask has been increasingly used, and a krypton fluoride (KrF) excimer laser light (248 nm) has been used as a light shorter in wavelength than the i ray. Moreover, the use of an argon fluoride (ArF) excimer laser light (193 rnm) or a fluorine dimer (F2) excimer laser light (157 nm) as a shorter wavelength light is also proposed.
With the shortening of the exposure wavelength, in the corresponding phase shift mask and phase shift mask blank, the control of transmittance, refractive index and other optical coefficients in the exposure wavelength for use becomes important. Different from visible to near ultraviolet areas, in the area with the wavelength shorter than 250 nm, since the degree of light absorption remarkably increases in many substances, it is difficult to control and obtain a desired transmittance. Therefore, the halftone phase shift mask for the i ray cannot usually be used as it is, as the halftone phase shift mask for the exposure light shorter than 250 nm. The transmittance in the halftone phase shifter is set depending on the sensitivity of the resist for use in the pattern transfer and the patterning process but, for example, in the halftone phase shift mask, it is preferable to control the transmittance of the exposure light in a range of 3% to 20% in the film thickness of the phase shifter for shifting the phase of the exposure light by a predetermined angle.
Moreover, even if the basic prescribed properties such as the transmittance and refractive index in the exposure wavelength are satisfied with the shortening of the exposure wavelength, no test can be performed with a high transmittance for the wavelength of test light (e.g., 364 nm, 488 nm, 633 nm), which is not suitable for practical use. Therefore, for the practical use, the transmittance is requested to be controlled to a desired value with respect to the wavelength of the test light.
Furthermore, in addition to the above-described properties, the halftone phase shift mask and the halftone phase shift mask blank as the mother material for forming the mask are requested to be stable against excimer laser irradiation for use (light-resistant), chemically durable in a cleaning process essential for the mask process (chemical-resistant) and to minimize micro defects in the blank which remarkably deteriorate the mask quality (low defect density).
Specifically, the shortening of the exposure wavelength also means that the density of the energy radiated per unit time increases. To cope with this, the film material for forming a phase shifter layer is requested not to deteriorate the function as the phase shift mask by damages caused by the high-energy irradiation. Here, the damages mean the change in optical properties (refractive index, transmittance, and the like) of the shifter film and the generation of color defects by the irradiation, film thickness changes, film quality deterioration, and the like. For example, when the excimer laser with the wavelength in a deep ultraviolet area is radiated, in-film substances are excited by a double photon process, this is said to cause changes in film optical properties and film quality, but details are not clarified. In any case, it is one of indispensable conditions that the phase shifter film is provided with a high resistance to irradiation in the high-energy irradiation with the shortening of the exposure wavelength.
Moreover, when the material of the shifter film is considered from the viewpoint of the mask material, the film must not be changed in properties or dissolved by cleaning by acids and alkalis in the mask forming process. Specifically, the phase shifter film requires the chemical resistance regardless of the size of the exposure wavelength.
Furthermore, considering that the phase shift mask is a tool for performing a fine processing, a fine processability is necessary so that the processing (patterning, etching, and the like) of the phase shift mask blank can be achieved with a high precision, and it is therefore requested that the phase shifter film be homogeneous and no defect be found in the film. It is said that the miniaturization of the mask pattern will further advance with the shortening of the exposure wavelength, and the defect in the phase shifter film raises an important problem which influences the reliability of the pattern transfer.
However, in the conventional halftone phase shift mask and blank, the basic prescribed properties such as the transmittance and refractive index with the shortening of the exposure wavelength, and all other above-described prescribed properties are not sufficiently achieved.
The present invention has been developed under the above-described background, and an object thereof is to provide a superior halftone phase shift mask for coping with a shortened exposure wavelength and the blank of the mask.
To achieve the aforementioned object, there are provided the following structures according to the present invention.
(Structure 1) A halftone phase shift mask blank for forming a phase shift mask, constituted by forming, on a transparent substrate, a semitransparent film provided with a function of producing a predetermined amount of phase difference in a light transmitted through the semitransparent film with respect to a light transmitted directly through the transparent substrate and a function of attenuating light intensity, in which the semitransparent film contains silicon, palladium, and at least one selected from nitrogen, oxygen and hydrogen.
(Structure 2) The halftone phase shift mask blank according to the structure 1 in which the total amount of silicon and palladium in the semitransparent film is in a range of 30 to 67 atom %.
(Structure 3) The halftone phase shift mask blank according to the structure 2 in which silicon and palladium contained in the semitransparent film are in a relation represented by the following equation (I):
[atom % of palladium in the film]/[(atom % of palladium in the film)+(atom % of silicon in the film)]xc3x97100=10 to 40(%)xe2x80x83xe2x80x83Equation (I).
(Structure 4) The halftone phase shift mask blank according to any one of the structures 1 to 3 in which at least one selected from nitrogen, oxygen and hydrogen contained In the semitransparent film forms a chemical bond to silicon.
(Structure 5) The halftone phase shift mask blank according to any one of the structures 1 to 4 in which the semitransparent film contains silicon, palladium, and nitrogen.
(Structure 6) The halftone phase shift mask blank according to the structure 5 in which the content of nitrogen in the semitransparent film is more than 0 and not more than 60 atom %.
(Structure 7) The halftone phase shift mask blank according to the structure 6 in which the content of nitrogen in the semitransparent film is more than 0 and not more than 50 atom %.
(Structure 8) The halftone phase shift mask blank according to any one of the structures 1 to 7 in which the semitransparent film contains oxygen in a range of 0 to 65 atom %.
(Structure 9) The halftone phase shift mask blank according to the structure 8 in which the semitransparent film contains oxygen in a range of 3 to 50 atom %.
(Structure 10) A halftone phase shift mask blank for forming a phase shift mask, constituted by forming, on a transparent substrate, a semitransparent film provided with a function of producing a predetermined amount of phase difference in a light transmitted through the semitransparent film with respect to a light transmitted directly through the transparent substrate and a function of attenuating light intensity,
in which the semitransparent film contains at least one element M selected from metals and transition metals (M denotes the metal or the transition metal other than palladium), silicon, palladium, and at least one selected from nitrogen, oxygen and hydrogen.
(Structure 11) The halftone phase shift mask blank according to the structure 10 in which the total amount of silicon and palladium in the semitransparent film is in a range of 30 to 67 atom %.
(Structure 12) The halftone phase shift mask blank according to the structure 10 or 11 in which said semitransparent film contains at least one element M selected from the metals and transition metals by more than 0 and not more than 20 atom %.
(Structure 13) The halftone phase shift mask blank according to the structure 12 in which silicon and palladium contained in the semitransparent film are in a relation represented by the following equation (II):
[atom % of palladium in the film]/[(atom % of palladium in the film)+(atom % of silicon in the film)]xc3x97100=5 to 40(%)xe2x80x83xe2x80x83Equation (II).
(Structure 14) The halftone phase shift mask blank according to any one of the structures 10 to 13 in which at least one selected from nitrogen, oxygen and hydrogen contained in the semitransparent film forms a chemical bond to silicon.
(Structure 15) The halftone phase shift mask blank according to any one of the structures 10 to 14 in which at least one element M selected from the metals or transition metals comprises at least one element selected from the group consisting of cobalt, tantalum, tungsten, molybdenum, chromium, vanadium, titanium, niobium, zinc, zirconium, hafnium, germanium, aluminum, platinum, manganese, and iron.
(Structure 16) The halftone phase shift mask blank according to any one of the structures 10 to 15 in which the semitransparent film contains at least one element M selected from the metals and transition metals, silicon, palladium, and nitrogen.
(Structure 17) The halftone phase shift mask blank according to the structure 16 in which the content of nitrogen in the semitransparent film is more than 0 and not more than 60 atom %.
(Structure 18) The halftone phase shift mask blank according to the structure 17 in which the content of nitrogen in the semitransparent film is more than 0 and not more than 50 atom %.
(Structure 19) The halftone phase shift mask blank according to any one of the structures 10 to 18 in which the semitransparent film contains oxygen in a range of 0 to 65 atom %.
(Structure 20) The halftone phase shift mask blank according to the structure 19 in which the semitransparent film contains oxygen in a range of 3 to 50 atom %.
(Structure 21) The halftone phase shift mask blank according to any one of the structures 1 to 20 in which the semitransparent film has a transmittance of 40% or less with respect to a desired test light in a test light wave range of 190 nm to 650 nm of the phase shift mask blank and phase shift mask.
(Structure 22) A method of manufacturing a halftone phase shift mask blank, comprising the steps of: using a sputtering target and a gas containing the constituting elements of the semitransparent film according to any one of the structures 1 to 21 and forming a semitransparent film on a transparent substrate by a sputtering method.
(Structure 23) The method of manufacturing the halftone phase shift mask blank according to the structure 22 in which the sputtering target contains silicon and palladium.
(Structure 24) The method of manufacturing the halftone phase shift mask blank according to the structure 23 in which silicon and palladium contained in the sputtering target are in a relation represented by the following equation (III):
[atom % of palladium]/[(atom % of palladium)+(atom % of silicon)]100=5 to 40(%)xe2x80x83xe2x80x83Equation (III).
(Structure 25) A method of manufacturing a halftone phase shift mask, comprising the steps of: subjecting the semitransparent film in the halftone phase shift mask blank according to any one of the structures 1 to 21 to an etching processing in dry etching using a chlorine containing gas and/or a fluorine containing gas.
(Structure 26) A halftone phase shift mask in which the halftone phase shift mask blank according to any one of the structures 1 to 21 is used, and a semitransparent mask pattern to be transferred to a wafer is formed on a transparent substrate.
(Structure 27) The halftone phase shift mask according to the structure 26 which is provided with a transmittance of 3% to 20% with respect to a desired exposure light in a wave range of 150 nm to 370 nm and which is subjected to an optical design to function as the phase shift mask.
(Structure 28) A pattern transfer method, comprising the steps of: using the halftone phase shift mask according to the structure 26 or 27 to perform a pattern transfer.
(Structure 29) A semiconductor device which is formed by using the halftone phase shift mask according to the structure 26 or 27 and performing the pattern transfer.
The basic condition of the present invention is that the use is possible with respect to the ultraviolet to deep ultraviolet exposure wave range. Therefore, the phase shifter film has to be provided with optical translucency with respect to the desired exposure wavelengths such as the oscillation wavelength of krypton fluoride excimer laser of 248 nm and the oscillation wavelength of argon fluoride excimer laser of 193 nm or other wavelengths, and this optical translucency has to be controllable in the film formation. Moreover, in addition to the optical translucency, the optical refractive index is necessary, and this optical refractive index has to be controllable similarly as the optical translucency. The refractive index is correlated with the film thickness of the phase shifter, and determines the phase shift angle as the important requirement of the phase shift mask. For example, when the refractive index is 2, the film thickness at which the phase shift angle of 180xc2x0 is obtained is 124 nm (xc3x97N: natural number) with the wavelength of 248 nm, and similarly 96.5 nm (xc3x97N: natural number) with the wavelength of 193 nm. Therefore, the desired optical translucency is actually required on the assumption that the film thickness condition for achieving the set phase shift angle is satisfied, and it is very important that these numeric values be controllable.
On the other hand, particularly in the present invention, by containing palladium and selecting and controlling the film composition (the constituting elements and the ratio) and film qualities (including the bond state and film structure), the semitransparent film can be obtained which satisfies the basic prescribed properties such as the transmittance and refractive index with respect to the exposure wavelength and which is additionally provided with the desired transmittance with respect to the desired test light in the test light wave range of 190 nm to 650 nm.
According to the above-described structure 1, when the semitransparent film contains silicon, palladium, and at least one selected from nitrogen, oxygen and hydrogen, all the prescribed properties of the halftone phase shift mask can be satisfied. Specifically, the semitransparent film of the structure 1 can satisfy the basic prescribed properties such as the transmittance and refractive index with respect to the exposure wavelength, and satisfy all other prescribed properties such as the transmittance with respect to the test light wavelength, optical resistance, chemical durability (resistance to chemicals) and low defect density.
According to the above-described structure 2, when the total amount of silicon and palladium in the semitransparent film is less than 30 atom %, the transmittance in the test light wave range is too high and it possibly becomes difficult to test the film. When the total amount of silicon and palladium in the semitransparent film exceeds 67 atom %, the transmittance in the exposure wave range is possibly deteriorated. From the similar viewpoint, the total amount of silicon and palladium in the semitransparent film is preferably in a range of 40 to 60 atom %.
Additionally, the content of silicon in the semitransparent film is preferably of the order of 30 to 55 atom %, more preferably 35 to 50 atom %. When the content of silicon is in this area, the strength of the semitransparent film is kept to be stable, and the film provided with the transmittance suitable for the exposure light is easily formed.
Moreover, the content of palladium in the semitransparent film is preferably of the order of 3 to 20 atom %, more preferably 4 to 15 atom %. When the content of palladium is in this range, particularly the required optical properties of the semitransparent film such as the transmittance and refractive index with respect to the light of the exposure wave range can easily be obtained, and the film provided with the transmittance suitable for the test light can easily be obtained. Furthermore, it is easy to form the semitransparent film also superior in the electric properties, chemical durability, and the like.
According to the above-described structure 3, when silicon and palladium contained in the semitransparent film are in a relation represented by the equation (I), the semitransparent film can easily satisfy all the prescribed properties of the halftone phase shift mask.
Additionally, when the ratio of [atom % of palladium in the film] to [atom % of palladium in the film+atom % of silicon in the film] is less than 10%, the transmittance rises in the entire wave range. On the other hand, the transmittance in the test light wave range is 40% or more, and it is substantially difficult to test the film. When the ratio exceeds 40%, the transmittance in the entire wave range, particularly in the vicinity of the exposure wavelength is lowered and the function as the halftone phase shifter is deteriorated. When the ratio of silicon to palladium is set in the above-described range, and at least one selected from nitrogen, oxygen and hydrogen is contained, the properties such as the transmittance and refractive index can be controlled.
According to the above-described structure 4, the semitransparent film satisfying the requirements of the above-described structures 1 to 3 preferably comprises an amorphous structure film containing an Sixe2x80x94N bond, Sixe2x80x94O bond, Sixe2x80x94H bond in order to control and improve the prescribed properties.
According to the above-described structure 5, when particularly nitrogen is contained as an essential component, it becomes easy to control the transmittance and refractive index of the semitransparent film and obtain the desired values.
According to the above-described structure 6, when the content of nitrogen in the semitransparent film exceeds 60 atom %, the transmittance rises in the entire wave range and it becomes difficult to perform the test. Furthermore, the film resistivity rises, and troubles such as film charge-up are brought about during the electron line drawing of the blank.
In the above-described structure 7, from the viewpoint similar to that of the above-described structure 6, the preferred content of nitrogen in the semitransparent film is further defined.
According to the above-described structure 8, when the content of oxygen in the semitransparent film exceeds 65 atom %, the transmittance rises in the entire wave range and the test becomes difficult to perform. Additionally, the film resistivity rises, the film refractive index is lowered, and the required electric and optical properties are not satisfied.
In the above-described structure 9, from the viewpoint similar to that of the structure 8, the preferred content of oxygen in the semitransparent film is further defined. Additionally, the content of oxygen is set to 3 atom % or more. When the content of oxygen is less than 3 atom %, the effect by oxygen of controlling the optical absorbency properties and optical transmission properties with good balance to obtain the desired semitransparent film cannot sufficiently be obtained.
According to the above-described structure 10, when the semitransparent film is constituted mainly of four or more elements including the metal and/or the transition metal M, silicon, palladium and at least one selected from nitrogen, oxygen and hydrogen, all the prescribed properties of the halftone phase shift mask can be satisfied.
Moreover, in the structure 10, by adding the metal and/or the transition metal, the prescribed properties can easily be controlled and improved.
In the above-described structure 11, when the total amount of silicon and palladium in the semitransparent film is less than 30 atom %, the transmittance in the test light wave range is too high and the film test possibly becomes difficult to perform. When the total amount of silicon and palladium in the semitransparent film exceeds 67 atom %, the transmittance in the exposure wave range is possibly deteriorated. From the similar viewpoint, the total amount of silicon and palladium in the semitransparent film is preferably in a range of 40 to 60 atom %.
Additionally, the content of silicon in the semitransparent film is preferably in a range of 30 to 55 atom %, more preferably 35 to 50 atom %. When the content of silicon is in this range, the strength of the semitransparent film is kept to be stable, and the film provided with the transmittance suitable for the exposure light is easily obtained.
Moreover, the content of palladium in the semitransparent film is preferably of the order of 3 to 20 atom %, more preferably 4 to 15 atom %. When the content of palladium is in this range, it is possible to easily obtain particularly the required optical properties of the semitransparent film such as the transmittance and refractive index with respect to the light of the exposure wave range, and the film provided with the transmittance suitable for the test light. Furthermore, it is easy to form the semitransparent film also superior in the electric properties, chemical durability, and the like.
In the above-described structure 12, when the content of the metal or the transition metal (element M) other than palladium exceeds 20 atoms %, the transmittance in the exposure wave range is possibly deteriorated.
Additionally, the total amount of silicon, palladium and element M in the semitransparent film is preferably in a range of 30 to 67 atom %. When the total amount is in this range, the required optical properties and chemical durability of the semitransparent film can easily be controlled, and the semitransparent film provided with the desired properties can easily be formed.
According to the above-described structure 13, when the semitransparent film contains the metal and/or the transition metal M, silicon, palladium, and at least one selected from nitrogen, oxygen and hydrogen, and the ratio of silicon and palladium contained in the semitransparent film is specified, all the prescribed properties of the halftone phase shift mask can be satisfied.
Additionally, when the ratio of [atom % of palladium in the film] to [atom % of palladium in the film+atom % of silicon in the film] is less than 5%, the transmission rises in the entire wave range. On the other hand, the transmittance in the test light wave range is 40% or more, and it is substantially difficult to test the film. When the ratio exceeds 40%, the transmittance in the entire wave range, particularly in the vicinity of the exposure wavelength is lowered and the function as the halftone phase shifter is deteriorated.
According to the above-described structure 14, the semitransparent film satisfying the requirements according to any one of the above-described structures 10 to 13 preferably comprises the amorphous structure film containing the Sixe2x80x94N bond, Sixe2x80x94O bond, Sixe2x80x94H bond in order to control and improve the prescribed properties.
According to the above-described structure 15, when these elements are used as the metals and/or the transition metals M, the desired optical properties can be achieved, and additionally the film electric properties, optical properties and chemical durability are effectively enhanced. Specifically, it is possible to achieve the enhancement of the film conductivity as the improvement of the electric properties, the transmittance control in the exposure wavelength and the improvement of the transmittance in the test light wave range as the improvement of the optical properties, and the improvement of the durability against acids and alkalis used in the mask cleaning process as the improvement of the chemical durability.
Additionally, among these elements, vanadium (V) is preferably contained. When vanadium is contained, the etching selection ratio of the semitransparent film with respect to the transparent substrate formed of quartz can further be enhanced.
According to the above-described structure 16, when particularly nitrogen is contained as the essential component, the transmittance and refractive index of the semitransparent film can easily be controlled to obtain the desired values.
According to the above-described structure 17, when the content of nitrogen in the semitransparent film exceeds 60 atom %, the transmittance rises in the entire wave range and the test becomes difficult to perform. Furthermore, the film resistivity rises, and the troubles such as film charge-up are brought about during the electron line drawing of the blank.
In the above-described structure 18, from the viewpoint similar to that of the structure 17, the preferred content of nitrogen in the semitransparent film is further defined.
According to the above-described structure 19, when the content of oxygen in the semitransparent film exceeds 65 atom %, the transmittance rises in the entire wave range and the test becomes difficult to perform. Additionally, the film resistivity rises, the film refractive index is lowered, and the required electric and optical properties are not satisfied.
In the above-described structure 20, from the viewpoint similar to that of the structure 19, the preferred content of oxygen in the semitransparent film is further defined. Additionally, the content of oxygen is set to 3 atom % or more. When the content of oxygen is less than 3 atom %, it is impossible to sufficiently obtain the effect by oxygen of controlling the optical absorbency properties and optical transmission properties with good balance to obtain the desired semitransparent film.
According to the above-described structure 21, when the film composition (the constituting elements and ratio) and film quality (including the bond state and film structure are selected and controlled in the above-described structures 1 to 20, the semitransparent film provided with the transmittance of 40% or less with respect to the desired test light in the test light wave range of 190 nm to 650 nm can be obtained. Therefore, the mask can be formed so that the highly reliable test can be performed.
In the above-described structure 22, when the breadth of film quality controllability and the mass productivity are considered, the semitransparent film is preferably formed by the sputtering method at present.
In the above-described structure 23, the sputtering target is defined so that silicon and palladium are preferably contained.
In the above-described structure 24, it is defined that silicon and palladium contained in the sputtering target are in a relation represented by the equation (III).
According to the above-described structure 25, the superior fine processability can be realized by combining the semitransparent film obtained in the present invention with the dry etching process using the chlorine containing gas and/or the fluorine containing gas.
According to the above-described structure 26, by patterning the blank, it is possible to obtain the halftone phase shift mask which satisfies all the prescribed properties.
According to the above-described structure 27, the halftone phase shift mask provided with the desired optical properties can be obtained. Particularly it is possible to obtain the halftone phase shift mask which are provided with the desired optical properties with respect to the exposure lights such as the krypton fluoride (KrF) excimer laser light (248 nm), the argon fluoride (ArF) excimer laser light (193 nm) and the fluorine dimer (F2) excimer laser light (157 nm).
According to the above-described structure 28, by using the halftone phase shift mask of the present invention to perform the pattern transfer, the transfer process for the shortened exposure wavelength can be realized.
According to the above-described structure 29, by using the halftone phase shift mask of the present invention to perform the pattern transfer, the semiconductor devices are obtained such as the semiconductor element to which the fine pattern for the shortened exposure wavelength is satisfactorily transferred.